1. Field of the Invention
The present invention relates to actuators and, more particularly, to an actuator for a crash valve located beneath a gasoline dispensing unit at a service station.
2. Description of Related Art
As is well known, the gasoline pumped through a dispensing unit at a gasoline service station is highly flammable and presents a very serious potential hazard. From time to time a driver may cause his vehicle to hit the dispensing unit with sufficient force to tilt or dislodge the dispensing unit from its mounting. The conduit conveying gasoline from an underground tank to the dispensing unit will be compromised or severed with a resulting outflow of gasoline. Unless such outflow is immediately checked, the outflow of gasoline will create an inferno if ignited. For this reason, a crash valve is located beneath the dispensing unit and through which the gasoline flows to the dispensing unit. The crash valve is designed to shear upon physical repositioning of the gasoline pump, which shearing automatically closes a valve and terminates further flow through the crash valve and into the dispensing unit. Thus, further flow of gasoline is terminated.
The shear valve is disposed within a sump or a liquid tight dispenser pan beneath the dispensing unit. This pan will collect any gasoline outflow as a result of leakage of gasoline from the crash valve or from any conduits or fittings within the dispensing unit. Additionally, the dispenser pan will collect any water flowing thereinto due to condensation, rain, or cleaning functions.
The presence of gasoline in the dispenser pan is an obvious hazard. The presence of water in the dispensing pan will have a corrosive effect upon both mechanical and electrical components of the crash valve and the apparatus within the dispensing unit due to the resulting humidity and likelihood of periodic condensation. Such corrosion, over a period of time, may compromise the integrity of the gasoline flow path with the obvious resulting safety hazard. Furthermore, the electrical and mechanical control elements attendant gasoline flow may be compromised over a period of time.
Presently, there are no known mechanical actuators responsive to either gasoline or a predetermined quantity of water within the dispenser pan for terminating flow of gasoline through the crash valve.
The present invention is a mechanical actuator operatively responsive to the presence of either gasoline or water within a dispenser pan located about a crash valve beneath a dispensing unit at a gasoline service station. The presence of gasoline, or any liquid hydrocarbon, will cause elongation of a porous cartridge. The elongation will reposition a plunger that dislodges a weight attached to a pivotable trip arm of the crash valve to terminate flow of gasoline therethrough upon pivotal movement. A float with attached pivoting arm will rise as the water level within the dispenser pan exceeds an acceptable level. The resulting movement of the pivoting arm will dislodge the weight and also result in pivotal movement of the trip arm to terminate flow of gasoline through the crash valve.
It is therefore a primary object of the present invention to provide an actuator for terminating flow through a crash valve in the presence of a liquid hydrocarbon or water.
Another object of the present invention is to provide a completely mechanical actuator responsive to either gasoline or water within a dispenser pan to cause termination of gasoline flow through a crash valve.
Yet another object of the present invention is to provide a simple translatable plunger actuated by an elongating cartridge responsive to the presence of gasoline for dislodging a weight to actuate a trip arm of a crash valve.
A further object of the present invention is to provide a simple float vertically responsive to the presence of water in a dispenser pan for dislodging a weight to actuate a trip arm of a crash valve.
A yet further object of the present invention is to provide an inexpensive mechanical actuator for terminating flow of gasoline through a crash valve upon the presence of gasoline or a predetermined amount of water in a dispenser pan within which the crash valve is located.
A yet further object of the present invention is to provide a method for terminating flow of gasoline through a crash valve upon the presence of gasoline or a predetermined amount of water proximate the crash valve.
These and other objects of the present invention will become apparent to those skilled in the art as the description of invention proceeds.